HotelTonight has announced two landmarks in its development, reaching three million downloads and offering its services in 50 cities.

New cities on offer for the service – which offers last minute hotel bookings – include Birmingham, Edinburgh, Glasgow, and Liverpool in the UK.

They join London, which was the first overseas destination offered by the service when added earlier this year ahead of the 2012 Olympic Games.

Hotels in Manchester and Salt Lake City will be added in early September.

HotelsTonight offers a similar service to Priceline and Hotwire, but as users literally have to wait until the night of the booking they are able to achieve the lowest rate available.

Discounts of more than 50 per cent are not uncommon with the app.